Moderate Democrats in San Francisco often complain that far-left politicians don't represent their values. Middle-class families are frustrated that their concerns - like safe streets - are undermined by ideologues with wild claims of a "police state." Developers are exasperated when their projects are subjected to endless delays, even when the property has been a vacant eyesore for years.

Would you like to see things change?

Then I've got some bad news for you.

You're going to have to get involved - or at least start paying attention.

The next two months will see a battle for the political soul of the city. It will pit the progressives against the moderates in a face-off that will have huge implications in the November elections and, perhaps, the election of the next mayor. The key is control of an obscure but incredibly influential organization called the Democratic County Central Committee.

Rather than complaining about the direction of the city, middle-of-the-road Democrats have to get active. They have to vote in the June DCCC election and they have to do their homework on the candidates to learn if they represent moderate values.

"If you want to see change in the city, change to the culture of the Board of Supervisors, and bring some common sense and reason back to the city, it starts with the DCCC," said David Latterman, a local pollster.

If you are not sure what the DCCC is, you are not alone.

"If you stopped people on the street and asked them what the DCCC was, most of them wouldn't know what you were talking about," Supervisor Michela Alioto-Pier said.

San Francisco political insiders know. The DCCC endorsement doesn't necessarily mean a win in every election - it just seems to work out that way. In 2008, the DCCC went 6-for-6 in supervisor races (the seventh, Ross Mirkarimi, used to belong to the Green Party and was not eligible for a Democratic endorsement) and 3-for-4 in the school board elections.

That's no surprise. San Francisco is a liberal Democrat town. When the official voice of the local Democratic committee sends out recommendations in mailers - and it has a nearly unlimited budget to do so - voters listen.

"But when Mrs. Jones receives her Democratic voter guide in the mail," said Scott Wiener, former chairman of the DCCC and candidate for supervisor in District Eight, "she's thinking of the party of Barack Obama, not the party of Aaron Peskin and (Supervisor) Chris Daly."

There's the rub. In 2008, Peskin and Daly unapologetically staged a takeover of the DCCC. They ran a slate of well-known names, including Eric Mar, David Campos and David Chiu, all of whom won seats as supervisors later that year. When they won seats on the DCCC, Wiener was voted out as chairman and replaced by Peskin, the former president of the Board of Supervisors.

Now, there's nothing illegal or evil about that. In fact, a few years ago people complained about then-Mayor Willie Brown controlling the DCCC. Peskin and Daly promised to dismantle the Willie Brown machine.

They did. Then they created their own.

"Aaron Peskin is building a political machine that would make Willie Brown blush," Wiener said.

Campos scoffs at that idea.

"We don't sit around trying to figure out what we, as a machine, should do," he said. "I talk to everybody."

Maybe so, but with the DCCC's unmistakable power, a progressive voting majority will guarantee endorsements of far-left candidates in the November elections for supervisor. And remember, if Gavin Newsom leaves office as mayor, the supervisors will elect his successor. The stakes are huge.

The election for the DCCC is in June. You should be sure to vote. And you should make sure you know who you are voting for.